How to speed up meshing with inside large FEMs

Hi All - I'm using NX Advanced sim (experianced user) and am noticing significant performance issues when creating large FEMs (> 300 MB). Issues releated to selecting large numbers of faces for meshing results in unreasonably long latency (in the order of hours). Also mesh updates are taking many hours when they should take < 60 seconds.

I think the tool is good for smaller problems but is almost unusable for larger FEMs. Do others notice this? Any tips to improve performance? Hardware is not the issue on my end....